Where cookies are stored

Cookie is a small piece of text information sent by the server to the browser in the HTTP response. The browser will store this information on the user's computer, specifically on the client or in the HTTP request. Detailed introduction: 1. Client, Cookie is stored on the client. The specific storage location depends on different browsers. In common browsers, Cookie can be stored in text files, databases and memory; 2. HTTP request , in each HTTP request, the browser will automatically compare it with the current domain name and so on.

The operating system for this tutorial: Windows 10 system, DELL G3 computer.

In web development, cookies are a mechanism used to pass data between the browser and the server. A cookie is a small piece of text information sent by the server to the browser in an HTTP response, and the browser stores this information on the user's computer. So, where are cookies stored specifically? Below I will explain in detail where cookies are stored.

1. Client:

Cookies are stored on the client (user computer). The specific storage location depends on different browsers. In common browsers, cookies can be stored in the following locations:

- Text files: In early browsers, cookies are usually stored in the form of text files on the hard drive of the user's computer. These text files are stored in specific folders based on the browser's profile directory. Different browsers may have different storage paths and file naming rules.

- Database: With the development of browsers, some modern browsers have begun to store cookies in the browser's database instead of in the form of text files. These databases can be SQLite, IndexedDB, etc. Cookies stored in the database are more secure and can be better managed and queried.

- Memory: Some browsers store cookies in memory, which means that cookies are only valid during the browser session and are cleared when the browser is closed. Cookies stored in memory are typically used to temporarily store session information or other temporary data.

It should be noted that no matter where cookies are stored, they are bound to a specific domain name. Cookies under each domain name are independent, and other domain names cannot access or modify these cookies.

2. HTTP request:

In each HTTP request, the browser will automatically add cookie information related to the current domain name to the request header so that the server can identify and process it. In this way, the server can perform personalized responses and processing based on the information in the cookie, such as user identity, session status, etc.

The cookie information in the request header is presented in the form of key-value pairs, such as "name=value". When the browser sends an HTTP request, it will add a field named "Cookie" to the request header, whose value is all cookie information related to the current domain name.

After receiving the request, the server can obtain relevant data by parsing the Cookie information in the request header, and perform corresponding processing as needed.

It should be noted that cookies are in clear text during storage and transmission, so sensitive information (such as passwords, personally identifiable information, etc.) should not be stored directly in cookies, but encryption or other security measures should be taken to protect data security. In addition, the storage capacity of cookies is also limited, and different browsers have different restrictions on the storage capacity of cookies.

In short, a cookie is a small piece of text information stored on the client. The specific storage location depends on different browsers. Whether stored in a text file, database, or memory, cookies are bound to a specific domain name and are passed between the browser and the server through HTTP requests. Proper use of cookies can realize user identity authentication, session management and other functions, providing users with a better personalized experience.

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